SSSS

SSSS is an initialism that can refer to several distinct concepts depending on context. The most prominent current usage in popular culture is the stylized title SSSS.Gridman, a 2018 anime series produced by Studio Trigger in collaboration with Tsuburaya Productions. The work reimagines the 1993 tokusatsu Gridman and explores themes of digital identity and heroism. The four S characters in the title are not officially defined by the creators and function mainly as branding.

In aviation security, SSSS stands for Secondary Security Screening Selection, a designation used by some authorities to identify passengers who will undergo enhanced screening at security checkpoints. The status is not universally applied and procedures vary by country and airport.

In other media, SSSS can appear as an acronym in titles or branding. A related property is the 1994 television series Superhuman Samurai Syber-Squad, commonly abbreviated as SSSSS (five S's), which is distinct from SSSS.Gridman despite a similar stylistic approach to naming.

As a letter string, SSSS is often used in branding, coding, or labeling where no standardized meaning is implied. Consequently, SSSS is best understood as a multi-use acronym rather than a single, fixed entity.